The present disclosure relates generally to well drilling operations and, more particularly, to rotary steerable systems.
Hydrocarbons, such as oil and gas, are commonly obtained from subterranean formations that may be located onshore or offshore. The development of subterranean operations and the processes involved in removing hydrocarbons from a subterranean formation may be complex. Typically, subterranean operations involve a number of different steps such as, for example, drilling a wellbore at a desired well site, treating the wellbore to optimize production of hydrocarbons, and performing the necessary steps to produce and process the hydrocarbons from the subterranean formation.
Drilling a wellbore may include introducing a drill bit into the formation and rotating the drill bit with a drill string. In certain operations, a steering system may be used to precisely locate the drill bit—both vertically and horizontally—in the formation. An example steering system is a rotary steerable system (RSS), which may perform the steering functions while the drill string and drill bit are rotating by altering the axis of the drill bit with respect to the wellbore. A point-the-bit system generally refers to an RSS in which an axis of the drill bit is altered with respect to the axis of the RSS. A push-the-bit system generally refers to an RSS in which hydraulic or other fluid-controlled pistons extend from the RSS and contact the wall of the borehole.
Both common RSS types may have design challenges related, for example, to maximizing reliability and minimizing maintenance, due to the complex mechanical/electrical/hydraulic elements used in their implementation. The pistons of the push-the-bit system, for example, include multiple seals that wear down over time as they are exposed to harsh downhole conditions. Once the seals fail, the RSS must be removed to the surface for repair, which factors into the overall expense of the drilling operation.
While embodiments of this disclosure have been depicted and described and are defined by reference to exemplary embodiments of the disclosure, such references do not imply a limitation on the disclosure, and no such limitation is to be inferred. The subject matter disclosed is capable of considerable modification, alteration, and equivalents in form and function, as will occur to those skilled in the pertinent art and having the benefit of this disclosure. The disclosed embodiments are provided by way of example only, and are not exhaustive of the scope of the disclosure.